Conductivity sensor

Abstract

A conductivity sensor includes a housing including a fluid inlet, a fluid outlet; and a chamber having an inner wall. The chamber is located between the fluid inlet and the fluid outlet. A conductivity sensor includes a first electrode. At least a portion of the first electrode is located in the chamber. The first electrode has a first longitudinal axis. The first electrode does not form any portion of the inner wall of the chamber. A conductivity sensor includes a second electrode. The second electrode forms at least a portion of the inner wall of the chamber. The second electrode has a second longitudinal axis. The first longitudinal axis is coaxial with the second longitudinal axis. A flow path of a fluid through the conductivity sensor is from the fluid inlet through the chamber to the fluid outlet.

1 . A conductivity sensor comprising:
 a housing comprising:
 a fluid inlet; 
 a fluid outlet; and 
 a chamber having an inner wall;
 wherein the chamber is located between the fluid inlet and the fluid outlet; 
 
   a first electrode;
 wherein at least a portion of the first electrode is located in the chamber; 
 wherein the first electrode has a first longitudinal axis; 
 wherein the first electrode does not form any portion of the inner wall of the chamber; and 
   a second electrode;
 wherein the second electrode forms at least a portion of the inner wall of the chamber; 
 wherein the second electrode has a second longitudinal axis; 
 wherein the first longitudinal axis is coaxial with the second longitudinal axis; 
   wherein a flow path of a fluid through the conductivity sensor is from the fluid inlet through the chamber to the fluid outlet.   
     
     
         2 . The conductivity sensor of  claim 1 , wherein the fluid inlet has a third longitudinal axis;
 wherein the fluid outlet has a fourth longitudinal axis;   wherein the third longitudinal axis is parallel to the fourth longitudinal axis; and   wherein the third longitudinal axis is offset from the fourth longitudinal axis.   
     
     
         3 . The conductivity sensor of  claim 2 , wherein the third longitudinal axis is coaxial with the first longitudinal axis. 
     
     
         4 . The conductivity sensor of  claim 1 , wherein an outer surface of the second electrode comprises a plurality of protrusions;
 wherein an inner surface of the housing comprises a plurality of grooves;   wherein the plurality of grooves is configured to receive the plurality of protrusions when the second electrode is installed in the housing.   
     
     
         5 . The conductivity sensor of  claim 1 , wherein at least one of the first electrode or the second electrode includes titanium. 
     
     
         6 . The conductivity sensor of  claim 1 , wherein the housing comprises an output connector configured to be connected to a processor. 
     
     
         7 . The conductivity sensor of  claim 6 , wherein the processor is configured to be secured to the housing. 
     
     
         8 . The conductivity sensor of  claim 1 , wherein a first end of the first electrode is configured to be disposed adjacent to a first end of the second electrode;
 wherein the first end of the second electrode is disposed downstream of a second end of the second electrode.   
     
     
         9 . The conductivity sensor of  claim 1 , wherein the first electrode is a first cylindrically shaped electrode having a first diameter,
 wherein the second electrode is a second cylindrically shaped electrode having a second diameter, and   wherein the second diameter is greater than the first diameter.   
     
     
         10 . The conductivity sensor of  claim 1 , wherein the conductivity sensor is configured to bring the fluid flowing through the chamber into contact with the first electrode and the second electrode. 
     
     
         11 . A dialysis system comprising:
 a water purification system configured to purify a fluid for use in dialysis;
 wherein the water purification system comprises:
 a conductivity sensor configured to sense a conductivity of the fluid for use in dialysis,
 wherein the conductivity sensor comprises: 
 
 
    a housing comprising:    a fluid inlet;    a fluid outlet; and    a chamber having an inner wall;    wherein the chamber is located between the fluid inlet and the fluid outlet;    a first electrode;    wherein at least a portion of the first electrode is located in the chamber,    wherein the first electrode does not form any portion of the inner wall of the chamber; and    a second electrode;    wherein the second electrode forms at least a portion of the inner wall of the chamber;    wherein a flow path of the fluid for use in dialysis through the conductivity sensor is from the fluid inlet through the chamber to the fluid outlet.   
     
     
         12 . The dialysis system of  claim 11 , wherein the first electrode has a first longitudinal axis;
 wherein the second electrode has a second longitudinal axis;   wherein the first longitudinal axis is coaxial with the second longitudinal axis; and   wherein the fluid outlet has a third longitudinal axis;
 wherein the third longitudinal axis is coaxial with the first longitudinal axis. 
   
     
     
         13 . The dialysis system of  claim 12 , wherein the fluid inlet has a fourth longitudinal axis; and wherein the third longitudinal axis is offset from the fourth longitudinal axis. 
     
     
         14 . The dialysis system of  claim 11 , wherein an outer surface of the second electrode comprises a plurality of protrusions;
 wherein an inner surface of the housing comprises a plurality of grooves;   wherein the plurality of grooves is configured to receive the plurality of protrusions when the second electrode is installed in the housing.   
     
     
         15 . The dialysis system of  claim 11 , wherein at least one of the first electrode or the second electrode includes titanium. 
     
     
         16 . The dialysis system of  claim 11 , wherein the housing comprises an output connector configured to be connected to a processor configured to secure the processor to the housing. 
     
     
         17 . The dialysis system of  claim 16 , wherein the processor is configured to be secured to the housing. 
     
     
         18 . The dialysis system of  claim 11 , wherein a first end of the first electrode is configured to be disposed adjacent a first end of the second electrode, wherein the first end of the second electrode is disposed downstream of a second end of the second electrode. 
     
     
         19 . The dialysis system of  claim 11 , comprising a second conductivity sensor configured to sense the conductivity of the fluid for use in dialysis at a different location in the water purification system than the conductivity sensor. 
     
     
         20 . The dialysis system of  claim 11 , wherein the conductivity sensor is configured to determine a first error condition in which a concentration of ions in the fluid for use in dialysis is greater than an ion concentration threshold.